Insulating material for electrical conductors.



W. E. COOK. INSULATING MATERIAL FOR ELECTRICAL cowoucrons. APPLlCATlONFILED APR. 24. 1911.

j; ATTORNEYS.

TUNE @ATS PATENT OFFICE,

WILLIAM. E. COOK, OF NEW YORK, N. Y., ASSIGNOR TO INSULATION DEVELOPMENTCORPORATION, A CORPORATION OF NEW YORK.

INSULATING MATERIAL FOR ELECTRICAL CONDUCTORS.

Specification of Letters Patent.

Patented Apr 29, 1919..

Application filed' April 24, 1917. Serial No. 164,308.

To all whom it may concern Be it known that I, IVILLIAM E. Coon, asubject of the King of the United Kingdom of Great Britain and Ireland.residing at St. George, in the borough of Richmond, city of New York,county of Richmond, and State of New York, have invented certain new anduseful Improvements in Insulating Material for Electrical Conductors, ofwhich the following is a specification, reference being had therein tothe accompanying drawings. which form a part thereof.

My invention relates to insulating material for electrical conductors,and more particularly to a matted, fibrous covering material for wiresadapted after application to a wire to be saturated or impregnated withan asphaltum or other composition for waterproofing the covering andincreasing its insulating efi'ect.

Heretofore conductor wires have been coated with a sliver of cottonwhich after being compacted and confined by a suitable braid has beenpassed through a bath of asphalt-um composition, as above described.This covering or wrapping of cotton sliver, is applied to a wire bymechanical means, and I have found, in actual practice, that thecapacity of the machine is very much reduced and uniformity of thequality of the insulation throughout is made impossible by reason of theimpossibility of increasing the speed of the machine because of theloose matting of the fibers of the sliver, and the tendency of thesliver to break, with a resultant loss of efiiciency even at fairly lowspeeds, or to attenuate, with a resultant variable thickness of theinsulation.

IVith these conditions in mind, I have produced an insulating materialwhich will retain therein all of the advantageous properties of avcotton sliver, that is its capability of quick absorption of theasphaltum composition, its ready compactibility about the wire whilepassing through the covering machine; and the adaptability of theoverlapping edges of the spirally Wound material to mat, whencompressed, to preserve continuity of the covering, and which inaddition thereto, will permit an increase of the speed of the coveringmachine Without likelihood of the attenuation of the sliver or of itsbreakage.

I secure these results by embedding in the sliver, as it leaves thecarding machine, a continuous strand of thread, cord or othernon-conductive material which has been previously coated with a suitableadhesive so as to be firmly bonded to the sliver in a manner to preventsuch sliver being gathered upon said strand with a resultant unching oraccumulation of the sliverat different points of the insulation uponthe\VlIQ.

As this insulating material is being applied to a wire, all stressesresulting in a feeding movement of. the material, will be applieddirectly to this inclosed strand, thus permitting an increase in thesestresses by an increased speed in the operation of the machine, to apoint limited only by the strength of this strand. IVith insulatingmaterial made in accordance with my invention, the capacity of thecovering machine may be increased eight or ten fold as compared with itsspeed when the insulating material is composed of a cotton sliverwithout the inclosed strand, bonded thereto.

The invention consists primarily in insulating material for electricalconductors consisting of a fibrous matted, absorbent body, consisting ofa strip or ribbon folded longitudinally upon, and about, a relativelysmaller continuous strand of non-conductive material and a binderbetween said body and said strand whereby movement of one relative tothe other, as the material is being applied to a conductor is prevented;and in such other novel characteristics as are hereinafter set forth anddescribed and more particularly pointed out in the claims heretoappended.

Referring to the drawings,

Figure 1 is a view of a short section of insulating material made inaccordance with my invention, with the strand indicated in dotted lines;and

Fig. 2 is a section on the line 22 of Fig. 1.

Like letters refer to like views.

In the accompanying drawings an indicates a sliver formed of cotton, thefibers of which lie longitudinally of the sliver and are looselymat-ted. Embedded in this mass of sliver bv having the opposite edges ofthe sliver foldct. upon each other, and about same, is a continuousstrand 6 preferably parts in both consisting of fairly heavy cottonthread or cord. This strand is fed within the sliver, as the sliverleaves the carding machine, and before coming into engagement with thesliver, it is coated with a suitable adhesive having no particularcharacteristics which specially adapt it for this use, so that thisstrand will be firmly bonded to the sliver preparatory to theapplication of the material to-a wire.

By using the strand 7), it is possible to make covering material for thewire of a cotton sliver ribbon of sufficient width and thickness toprovide an insulation for the wire of the desired thickness, and topremit the rapid covering of the wire therewith. Furthermore, by havingthe fibers very loosely matted, compaction of this mass about the wireis facilitated.

As the material is applied to the wire, the strand Z) will control thefeeding movement of the material, thus effectively preventing theattenuation, or the breakage, of this sliver a. The application of thisstrand will not interfere in any way with the desired compaction of thesliver upon the wire, or have any substantial effect in modifying theabsorptive properties of the sliver after it has been applied to thewire. In fact, in addition to facilitating the application of thematerial to the wire, this strand serves as a binding means forretaining the sliver upon the wire even after it has been saturated, orimpregnated with an asphaltum composition, and will aid in compactingthe fibrous material upon the wire as it is wrapped about same in thecovering machine.

I have found it essential to embed this strand in loosely matted fibersand to bond it thereto in the manner above described.

Insulating material of the character herein described, while beingcapable of use in producing the ordinary insulated wire, having abraided covering, is particularly adapted for use with insulated wire inwhich this braid is dispensed with.

Having described the invention, what I Copies of this patent may smallercontinuous he obtained for five cents each, by addressing isoaois claimas new and desire to have protected by Letters Patent is 1. Insulatingmaterial for electrical conductors consisting of a strip or ribbonhaving a fibrous, matted, absorbent body folded longitudinally thereofupon, and about. a relatively smaller continuous strand of flexible,non-conductive material and a binder between said body and said strandwhereby movementof one relative to the other, as the material is beingapplied to a conductor, is prevented.

2. Insulating material for electrical conductors consisting of a stripor ribbon formed of cotton sliver folded longitudinally thereof upon andabout and bonded to a relatively smaller continuous strand of flexible,non-conductive material.

3. Insulating material for electrical conductors consisting of a stripor ribbon of cotton sliver folded longitudinally thereof upon and aboutand bonded to a relatively strand of flexible, non conductive material,the fibers of said sliver at ending longitudinally of the strip or rib-4. Insulating material for electrical conductors consisting of a stripor ribbon of cotton sliver, the edges of which are folded upon eachother, and about a relatively smaller thread or cord, and an adhesivebinder between said sliver and said thread or cord.

5. Insulating mate-rial for electrical conductors consisting of a stripor ribbon of cotton sliver, the edges of which are folded upon eachother and about. a relatively smaller thread or cord, and an adhesivebinder between said sliver and said thread or cord, the fibers of saidsliver extending longitudinally of said thread or cord.

In witness whereof, I hereunto aflix my signature, in the presence oftwo subscribing witnesses, this 9th day of April 1917.

IVILIJIAM E. COOK. \Vitnesses:

BERTHE MUELLER. CLARICE FRANCK.

the Commissioner ct Patents,

Washington, 10. G.

